Some patients who underwent neuronal transplantation after stroke showed
improvement in motor function, according to Douglas Kondziolka, MD, professor
of neurological surgery and radiation oncology at the University of Pittsburgh
department of neurological surgery. His study, presented at the annual
meeting of the American Association of Neurological Surgeons in San Francisco,
reported on the 6-month neurologic outcome and 12- to 18-month safety data
of patients in the first research study of a treatment aimed at reversing
neurological deficits from stroke.

Dr. Kondziolka's study involved 12 patients in a phase I trial that
evaluated the safety and feasibility of implanting human neuronal cells
for treatment of chronic stroke in the basal ganglia region of the brain.

The 9 men and 3 women in the study varied in age from 44 to 75 years.
In 8 patients, the stroke involved only the basal ganglia region of the
brain and in 4 patients, both the basal ganglia and regional cortex were
involved. All patients had stable neurologic deficits at least 2 months
prior to implantation.

The first 4 patients were treated with 2 million neurons implanted at
3 sites along a single needle pass within the basal ganglia. The remaining
8 patients were randomized to receive either 2 million neurons along a
single needle pass or a total of 6 million neurons implanted along 3 trajectories.

Assessment of safety and feasibility was performed using the NIH Stroke
Scale (NIHSS), European Stroke Scale (ESS), Short Form 36 (SF36), and Barthel
Index (BI).

Following implantation, subjective improvement, which included increased
strength, sensation, and coordination, was reported in 8 patients.

Objectively, 6 patients had an increase in ESS score ranging from 3
to 10 points, with 4 of these patients improving by 8 or more points. Three
patients had no change from their baseline scores, and 3 patients deteriorated
slightly. Six patients improved from 1 to 8 points on the motor component
of ESS with 4 patients improving 6 points or more.

"The changes in performance on the motor function of each of these scales
accounted for the majority of improvement noted," reported Dr. Kondziolka.
"Functional improvement appeared to be independent of the time interval
since occurrence of the strokes. Increases in cerebral glucose metabolism
as measured by PET scanning appeared to correlate with functional improvement."

The implanted human neuronal cells are provided by Layton BioScience,
Inc, located in Atherton, Calif. The neuronal cells originate from a human
teratocarcinoma, a tumor of the reproductive organs that is composed of
embryonic-like cells, removed from a 22-year-old cancer patient in the
early 1980s. Layton BioScience has licensed a patented process that uses
several chemicals to transform this cell line into the fully differentiated
nondividing human neuronal cells that can be used in clinical applications.
In extensive preclinical testing, implants of of the neuronal cells reversed
cognitive and motor deficits in animals in which stroke had been induced.

The procedure begins with the placement of a stereotactic frame on the
head of the patient. The frame is a standard tool in neurosurgery to provide
a fixed way to find specific locations within the brain. The patient then
receives a CT or MRI scan of the brain and the surgical team makes its
final decision for location of cell implantation.

Concurrently, the University of Pittsburgh Immunologic Monitoring and
Diagnostic Laboratory team thaws the human neuronal cells that were frozen
by and transported from Layton BioScience.

After the cells are transferred to a long-needled syringe, the surgeon
uses CT to guide their injection at multiple sites. The surgeon injects
these cells through a small opening in the skull, and patients generally
leave the hospital the next day. Dr. Kondziolka will soon begin a second,
much larger multicenter trial to assess the effectiveness of the treatment.